Curable resin composition, electrophotographic photoreceptor, process cartridge and image forming apparatus

Abstract

A curable resin composition for use as a constituent material of an electrophotographic photoreceptor, the curable resin composition comprising: a phenolic resin having an (MwH/MwL) value of approximately 1.90 or less in a molecular weight distribution measured by gel permeation chromatography, wherein MwH is a peak area for a weight average molecular weight of approximately 200 or more; and MwL is a peak area for a weight average molecular weight of less than approximately 200.

1 . A curable resin composition for use as a constituent material of an electrophotographic photoreceptor, the curable resin composition comprising: 
 a phenolic resin having an (MwH/MwL) value of approximately 1.90 or less in a molecular weight distribution measured by gel permeation chromatography,    wherein MwH is a peak area for a weight average molecular weight of approximately 200 or more; and    MwL is a peak area for a weight average molecular weight of less than approximately 200.    
     
     
         2 . The curable resin composition according to  claim 1 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 1.50 or less.    
     
     
         3 . The curable resin composition according to  claim 1 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 0.20 or more.    
     
     
         4 . The curable resin composition according to  claim 1 , further comprising a charge transport material.  
     
     
         5 . The curable resin composition according to  claim 4 , 
 wherein the charge transport material comprises at least one compound represented by formula (I), (II), (III), (IV) or (V):      F[—D—Si(R 1 ) (3-a) Q a ] b    (I)    in formula (I), F denotes an organic group derived from a compound having hole transporting ability; D denotes a bivalent group having flexibility; R 1  denotes a hydrogen atom, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; Q denotes a hydrolyzable group; a denotes an integer from 1 to 3; and b denotes an integer from 1 to 4;      F[—(X 1 ) n1 R 2 —Z 1 H] m1    (II)    in formula (II), F denotes an organic group derived from a compound having hole transporting ability; R 2  denotes an alkylene group; Z 1  denotes an oxygen atom, a sulfur atom, NH or COO; X 1  denotes an oxygen atom or a sulfur atom; m1 denotes an integer from 1 to 4; and n1 denotes 0 or 1;      F[—(X 2 ) n2 —(R 3 ) n3 —(Z 2 ) n4 G] n5    (III)    in formula (III), F denotes an organic group derived from a compound having hole transporting ability; X 2  denotes an oxygen atom or a sulfur atom; R 3  denotes an alkylene group; Z 2  denotes an oxygen atom, a sulfur atom, NH or COO; G denotes an epoxy group; n2, n3 and n4 each independently denotes 0 or 1; and n5 denotes an integer from 1 to 4;                          in formula (IV), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; Y denotes an oxygen atom or a sulfur atom; R 4 , R 5  and R 6  each independently denotes a hydrogen atom or a monovalent organic group; R 7  denotes a monovalent organic group; m2 denotes 0 or 1; and n6 denotes an integer from 1 to 4; provided that R 6  and R 7  may be bonded together to form a heterocyclic ring having Y as a hetero atom;                          in formula (V), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; R 8  denotes a monovalent organic group; m3 denotes 0 or 1; and n7 denotes an integer from 1 to 4.    
     
     
         6 . An electrophotographic photoreceptor comprising: 
 a conductive support; and    a photosensitive layer provided on the conductive support,    wherein the photosensitive layer comprises a functional layer comprising a cured substance of a curable resin composition, and the curable resin composition comprising:    a phenolic resin having an (MwH/MwL) value of approximately 1.90 or less in a molecular weight distribution measured by gel permeation chromatography,    wherein MwH is a peak area for a weight average molecular weight of approximately 200 or more; and    MwL is a peak area for a weight average molecular weight of less than approximately 200.    
     
     
         7 . The electrophotographic photoreceptor according to  claim 6 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 1.50 or less.    
     
     
         8 . The electrophotographic photoreceptor according to  claim 6 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 0.20 or more.    
     
     
         9 . The electrophotographic photoreceptor according to  claim 6 , 
 the curable resin composition further comprises a charge transport material.    
     
     
         10 . The electrophotographic photoreceptor according to  claim 9 , 
 wherein the charge transport material comprises at least one compound represented by formula (I), (II), (III), (IV) or (V):      F[—D—Si(R 1 ) (3-a) Q a ] b    (I)    in formula (I), F denotes an organic group derived from a compound having hole transporting ability; D denotes a bivalent group having flexibility; R 1  denotes a hydrogen atom, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; Q denotes a hydrolyzable group; a denotes an integer from 1 to 3; and b denotes an integer from 1 to 4;      F[—(X 1 ) n1 R 2 —Z 1 H] m1    (II)    in formula (II), F denotes an organic group derived from a compound having hole transporting ability; R 2  denotes an alkylene group; Z 1  denotes an oxygen atom, a sulfur atom, NH or COO; X 1  denotes an oxygen atom or a sulfur atom; m1 denotes an integer from 1 to 4; and n1 denotes 0 or 1;      F[—(X 2 ) n2 —(R 3 ) n3 —(Z 2 ) n4 G] n5    (III)    in formula (III), F denotes an organic group derived from a compound having hole transporting ability; X 2  denotes an oxygen atom or a sulfur atom; R 3  denotes an alkylene group; Z 2  denotes an oxygen atom, a sulfur atom, NH or COO; G denotes an epoxy group; n2, n3 and n4 each independently denotes 0 or 1; and n5 denotes an integer from 1 to 4;                          in formula (IV), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; Y denotes an oxygen atom or a sulfur atom; R 4 , R 5  and R 6  each independently denotes a hydrogen atom or a monovalent organic group; R 7  denotes a monovalent organic group; m2 denotes 0 or 1; and n6 denotes an integer from 1 to 4; provided that R 6  and R 7  may be bonded together to form a heterocyclic ring having Y as a hetero atom;                          in formula (V), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; R 8  denotes a monovalent organic group; m3 denotes 0 or 1; and n7 denotes an integer from 1 to 4.    
     
     
         11 . A process cartridge comprising: 
 an electrophotographic photoreceptor; and    at least one selected from the group consisting of a charging device that charges the electrophotographic photoreceptor, developing device that developes an electrostatic latent image, which is formed on the electrophotographic photoreceptor, with a toner to form a toner image and cleaning device that removes a toner remaining on a surface of the electrophotographic photoreceptor,    wherein the electrophotographic photoreceptor comprising:    a conductive support; and    a photosensitive layer provided on the conductive support,    wherein the photosensitive layer comprises a functional layer comprising a cured substance of a curable resin composition, and the curable resin composition comprising:    a phenolic resin having an (MwH/MwL) value of approximately 1.90 or less in a molecular weight distribution measured by gel permeation chromatography,    wherein MwH is a peak area for a weight average molecular weight of approximately 200 or more; and    MwL is a peak area for a weight average molecular weight of less than approximately 200.    
     
     
         12 . The process cartridge according to  claim 11 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 1.50 or less.    
     
     
         13 . The process cartridge according to  claim 11 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 0.20 or more.    
     
     
         14 . The process cartridge according to  claim 11 , 
 the curable resin composition further comprises a charge transport material.    
     
     
         15 . The process cartridge according to  claim 14 , 
 wherein the charge transport material comprises at least one compound represented by formula (I), (II), (III), (IV) or (V):      F[—D—Si(R 1 ) (3-a) Q a ] b    (I)    in formula (I), F denotes an organic group derived from a compound having hole transporting ability; D denotes a bivalent group having flexibility; R 1  denotes a hydrogen atom, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; Q denotes a hydrolyzable group; a denotes an integer from 1 to 3; and b denotes an integer from 1 to 4;      F[—(X 1 ) n1 R 2 —Z 1 H] m1    (II)    in formula (II), F denotes an organic group derived from a compound having hole transporting ability; R 2  denotes an alkylene group; Z 1  denotes an oxygen atom, a sulfur atom, NH or COO; X 1  denotes an oxygen atom or a sulfur atom; m1 denotes an integer from 1 to 4; and n1 denotes 0 or 1;      F[—(X 2 ) n2 —(R 3 ) n3 —(Z 2 ) n4 G] n5    (III)    in formula (III), F denotes an organic group derived from a compound having hole transporting ability; X 2  denotes an oxygen atom or a sulfur atom; R 3  denotes an alkylene group; Z 2  denotes an oxygen atom, a sulfur atom, NH or COO; G denotes an epoxy group; n2, n3 and n4 each independently denotes 0 or 1; and n5 denotes an integer from 1 to 4;                          in formula (IV), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; Y denotes an oxygen atom or a sulfur atom; R 4 , R 5  and R 6  each independently denotes a hydrogen atom or a monovalent organic group; R 7  denotes a monovalent organic group; m2 denotes 0 or 1; and n6 denotes an integer from 1 to 4; provided that R 6  and R 7  may be bonded together to form a heterocyclic ring having Y as a hetero atom;                          in formula (V), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; R 8  denotes a monovalent organic group; m3 denotes 0 or 1; and n7 denotes an integer from 1 to 4.    
     
     
         16 . An image forming apparatus comprising: 
 an electrophotographic photoreceptor;    charging device that charges the electrophotographic photoreceptor;    exposing device that formes an electrostatic latent image on the charged electrophotographic photoreceptor;    developing device that developes the electrostatic latent image with a toner to form a toner image; and    transfer device that transfers the toner image from the electrophotographic photoreceptor onto a transfer medium,    wherein the electrophotographic photoreceptor comprising:    a conductive support; and    a photosensitive layer provided on the conductive support,    wherein the photosensitive layer comprises a functional layer comprising a cured substance of a curable resin composition, and the curable resin composition comprising:    a phenolic resin having an (MwH/MwL) value of approximately 1.90 or less in a molecular weight distribution measured by gel permeation chromatography,    wherein MwH is a peak area for a weight average molecular weight of approximately 200 or more; and    MwL is a peak area for a weight average molecular weight of less than approximately 200.    
     
     
         17 . The image forming apparatus according to  claim 16 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 1.50 or less.    
     
     
         18 . The image forming apparatus according to  claim 16 , 
 wherein the (MwH/MwL) value of the phenolic resin is approximately 0.20 or more.    
     
     
         19 . The image forming apparatus according to  claim 16 , 
 the curable resin composition further comprises a charge transport material.    
     
     
         20 . The image forming apparatus according to  claim 19 , 
 wherein the charge transport material comprises at least one compound represented by formula (I), (II), (III), (IV) or (V):      F[—D—Si(R 1 ) (3-a) Q a ] b    (I)    in formula (I), F denotes an organic group derived from a compound having hole transporting ability; D denotes a bivalent group having flexibility; R 1  denotes a hydrogen atom, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; Q denotes a hydrolyzable group; a denotes an integer from 1 to 3; and b denotes an integer from 1 to 4;      F[—(X 1 ) n1 R 2 —Z 1 H] m1    (II)    in formula (II), F denotes an organic group derived from a compound having hole transporting ability; R 2  denotes an alkylene group; Z 1  denotes an oxygen atom, a sulfur atom, NH or COO; X 1  denotes an oxygen atom or a sulfur atom; m1 denotes an integer from 1 to 4; and n1 denotes 0 or 1;      F[—(X 2 ) n2 —(R 3 ) n3 —(Z 2 ) n4 G] n5    (III)    in formula (III), F denotes an organic group derived from a compound having hole transporting ability; X 2  denotes an oxygen atom or a sulfur atom; R 3  denotes an alkylene group; Z 2  denotes an oxygen atom, a sulfur atom, NH or COO; G denotes an epoxy group; n2, n3 and n4 each independently denotes 0 or 1; and n5 denotes an integer from 1 to 4;                          in formula (IV), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; Y denotes an oxygen atom or a sulfur atom; R 4 , R 5  and R 6  each independently denotes a hydrogen atom or a monovalent organic group; R 7  denotes a monovalent organic group; m2 denotes 0 or 1; and n6 denotes an integer from 1 to 4; provided that R 6  and R 7  may be bonded together to form a heterocyclic ring having Y as a hetero atom;                          in formula (V), F denotes an organic group derived from a compound having hole transporting ability; T denotes a bivalent group; R 8  denotes a monovalent organic group; m3 denotes 0 or 1; and n7 denotes an integer from 1 to 4.